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21.
Plant-derived antioxidant compounds have the potential to prevent cell damage caused by free radicals. As a holoparasitic plant, Cuscuta campestris Yuncker is being valorized for treatment of liver injury and cancer prevention in traditional medicine. The main purpose of this present study is to elucidate the antioxidant- and anticancer-associated contents of C. campestris by spectroscopic and chromatographic methods. Diethyl ether, ethyl acetate, methanol, n-butanol, and water were used as extraction solvents to reach a wide range of secondary metabolites synthesized by this plant. Antioxidant potentials of these extracts were characterized by (2,2-diphenyl-1-picrylhydrazyl)-free radical scavenging activity. Their anticancer activities were evaluated on SNU-398 hepatocellular carcinoma cells and controlled on the normal adult human dermal fibroblasts (hDFs) cells. Their phenolic compounds were analyzed by high-performance liquid chromatography with diode array detector to illuminate the responsible anticancer agent(s). The ethyl acetate extract revealed the most significant antioxidant effect. Methanol and ethyl acetate extracts were found to be cytotoxic on the SNU-398 cell lines with CC50 values of 18.7 and 19.6?µg?mL?1, respectively, whereas these extracts were not cytotoxic to the adult hDFs cells. Due to their abundance in the extracts, isorhamnetin, kaempferol, and quercetin may have caused this anticancer activity. Methanol extract has the highest concentration of phenolic compounds. Based on chromatographic analyses, we propose that these anticancer effects were positively correlated with plant phenolic compounds. The results showed that this plant is worth further study for its therapeutic uses. 相似文献
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Kaleeswari Kalairajan Tamil Selvi Arunachalam 《Research on Chemical Intermediates》2022,48(4):1495-1513
Research on Chemical Intermediates - A straightforward and suitable protocol is described for the conversion of substituted styrene to alkylbenzenes in the presence of Al2O3 nanoparticles... 相似文献
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We are reporting on the synthesis of Mn3O4 nanoparticles and CTAB-Mn3O4 nanocomposites via a sonochemical route using MnCl2, ethanol, NaOH and CTAB. The crystalline phase was identified as Mn3O4. The crystallite size of the CTAB-Mn3O4 nanocomposite was identified as 13 ± 5 nm from X-ray line profile fitting and the particle size from TEM was 107.5 ± 1.4 nm. The interaction between CTAB and the Mn3O4 nanoparticles was investigated by FTIR and 1H NMR spectroscopies. Two different magnetic phase transitions were observed for both samples below the Curie temperature (43 °C) by using a low temperature Electron Paramagnetic Resonance (EPR) technique. Also we determined the effect of the capping with CTAB on the reduction in absorbed power. 相似文献
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Funda Ozyurt Asuman Durmus E. Gorkem Gunbas Levent Toppare 《Journal of Solid State Electrochemistry》2010,14(2):279-283
Electrochemical copolymerization of 2,3-bis(4-tert-butylphenyl)-5,8-bis(4-hexylthiophen-2-yl)quinoxaline (HTQ) and 3,4-ethylenedioxythiophene (EDOT) was performed to fulfill
a strategy in achieving fine-tuned electrochromic properties. The copolymer, P(HTQ-co-EDOT) was characterized via detailed studies of cyclic voltammetry and spectroelectrochemistry. Copolymer film has many superior
properties compared to the parent homopolymer. E
g
of the copolymer was calculated as 1.4 eV, which is substantially lower than the homopolymer’s (PHTQ) band gap, which was
reported as 1.75 eV. Optical contrast of the resultant copolymer was shown to be 34%, which is nearly 10% higher than the
PHTQ. The most striking achievement in the electrochromic properties was in switching times. The copolymer switches very rapidly
between its neutral and the oxidized states and achieves a 34% optical contrast in less than 1 s, half of the value for the
pristine polymer. 相似文献
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M. Yogavel P. G. Aravindan D. Velmurugan K. Sekar S. Selvi P. T. Perumal S. Shanmuga Sundara Raj H.‐K. Fun 《Acta Crystallographica. Section C, Structural Chemistry》2003,59(7):o394-o396
In the title compounds, C13H15N3O, (I), and C13H15N3O2, (II), the dihedral angles between the planes of the phenyl ring and the amide group are 4.1 (1) and 20.7 (1)°, respectively. The molecules adopt a fully extended conformation, aided by intramolecular interactions. The molecular structures of (I) and (II) display different crystal packing and hydrogen‐bonding networks. 相似文献
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Development and investigation of the flexible hydrogen sensor based on ZnO-decorated Sb2O3 nanobelts
Natarajan Pradeep Gopal Tamil Selvi Uma Venkatraman Quyet Van Le Soon Kwan Jeong Saravanan Pandiaraj Abdullah Alodhayb Muthumareeswaran Muthuramamoorthy Andrews Nirmala Grace 《Materials Today Chemistry》2021
Hydrogen is regarded as the next-gen fuel for vehicles to avoid the emission of toxic gases, which needs a continuous monitoring of the concentration level. In the design of the H2 sensor, especially of flexible type, a sensing layer will be blended, which affects the sensing performance of the device. Based on this concern, the present investigation is carried out to understand the effect of the bending angle toward the sensing performance of bare and ZnO (n-type)-decorated Sb2O3 (p-type) nanobelt–based sensors for hydrogen gas. The sensing element was prepared by the thermal chemical vapor deposition followed by the drop-casting method. Furthermore, the role of the zinc precursor (molar concentration—1 M–3 M) on the preparation of ZnO-decorated Sb2O3 nanobelts was studied. Various techniques were used to confirm the formation of ZnO-decorated nanobelts such as X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray analysis (EDAX), and Fourier transform infrared spectroscopy (FTIR). From these analyses, 1 M concentration of the zinc precursor shows uniform distribution of nanoparticles over the surface of Sb2O3 nanobelts. However, agglomeration was observed when the concentration of the zinc precursor increases from 1 M to 3 M. Later, the prepared nanobelts were deposited on the OverHead Projector (OHP) sheet by the doctor blade method for sensing hydrogen gas at 100 °C at a concentration of 1000–3000 ppm. In addition to it, the effect of the substrate bending angle (0°, 45°, 60°, and 90°) was analyzed at a fixed concentration of H2 gas (1000 ppm). From this study, it is clear that the highest sensing response was achieved for 1 M decorated nanobelts compared with bare as well as other concentrations because of uniform distribution of nanoparticles on the surface of nanobelts. Moreover, the prepared sample demonstrates better sensing performance with the bending of substrates, which suggests that the prepared sensor could be used for flexible electronic devices. The prepared nanobelts show a good H2 gas–sensing response even with bending of the substrates. The work suggests that the prepared sensor is applicable for flexible electronic devices. 相似文献
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N.Yu. Agafonova M. Aglietta P. Antonioli G. Bari A. Bonardi V.V. Boyarkin G. Bruno W. Fulgione P. Galeotti M. Garbini P.L. Ghia P. Giusti E. Kemp V.V. Kuznetsov V.A. Kuznetsov A.S. Malguin H. Menghetti R. Persiani A. Pesci I.A. Pless A. Porta V.G. Ryasny O.G. Ryazhskaya O. Saavedra G. Sartorelli M. Selvi C. Vigorito L. Votano V.F. Yakushev G.T. Zatsepin A. Zichichi 《The European Physical Journal C - Particles and Fields》2007,52(4):849-855
The CERN Neutrino to Gran Sasso (CNGS) project aims to produce a high energy, wide band νμ beam at CERN and send it toward the INFN Gran Sasso National Laboratory (LNGS), 732 km away. Its main goal is the observation
of the ντ appearance, through neutrino flavour oscillation. The beam started its operation in August 2006 for about 12 days: a total
amount of 7.6×1017 protons were delivered to the target. The LVD detector, installed in hall A of the LNGS and mainly dedicated to the study
of supernova neutrinos, was fully operating during the whole CNGS running time. A total number of 569 events were detected
in coincidence with the beam spill time. This is in good agreement with the expected number of events from Monte Carlo simulations.
PACS 14.60.Pq; 29.27.Fh; 29.40.Mc; 95.55.Vj 相似文献
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AbstractThe flame-retardant behavior of organic polymers is considered as very important criteria to utilize them in the form of coatings, encapsulants, sealants, and matrices for high performance industrial applications. A new type of poly (benzoxazine-co-urethane) (PBZ-co-PU) matrices have been developed using dimethylol benzoxazine monomers (BZM and BZE) and tris(p-isocyanatophenyl)thiophosphate (Desmodur) through A2?+?B3 approach followed by thermal curing. The molecular structure of developed PBZ-co-PU was confirmed by FT-IR spectra and their thermal stability and flame retardant behavior were studied by standard methods. Data obtained from TGA and DSC, indicate that the PBZ-co-PU possesses higher Tg, better thermal stability and LOI than those of neat PBZ. Further, it was also observed that among the two matrix systems (PBZ-co-PU-1 and PBZ-co-PU-2) studied, the PBZ-co-PU-1 based system exhibited higher Tg, thermal stability and flame retardant behavior than those of PBZ-co-PU-2. 相似文献